A convex polygon is one in which no part of a line segment is connecting any two points on the polygon is outside the polygon.
A concave polygon does not have this characteristic. ( in some cases the word polygon will mean a convex polygon unless othewise stated)
Sum of the interior angles of a Polygon-180
Sum of the exterior angles of a polygon-360

Concave Polygon
Concave Polygon
Convex polygon
Convex polygon


The formula to find the measure of and interior angle of a regular polygon is (n-2)(180)divided by n

the formula for the sum of interior angles of a polygon-(n-2)(180)